/**
 * Copyright 2010-present Facebook.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.facebook.internal;

import android.content.Context;
import android.net.Uri;

import java.net.URI;
import java.net.URISyntaxException;

public class ImageRequest
{

  public interface Callback
  {
    /**
     * This method should always be called on the UI thread. ImageDownloader makes
     * sure to do this when it is responsible for issuing the ImageResponse
     *
     * @param response
     */
    void onCompleted(ImageResponse response);
  }

  public static final int UNSPECIFIED_DIMENSION = 0;

  private static final String PROFILEPIC_URL_FORMAT =
      "https://graph.facebook.com/%s/picture";
  private static final String HEIGHT_PARAM = "height";
  private static final String WIDTH_PARAM = "width";
  private static final String MIGRATION_PARAM = "migration_overrides";
  private static final String MIGRATION_VALUE = "{october_2012:true}";

  private Context context;
  private URI imageUri;
  private Callback callback;
  private boolean allowCachedRedirects;
  private Object callerTag;

  public static URI getProfilePictureUrl(
      String userId,
      int width,
      int height)
      throws URISyntaxException
  {

    Validate.notNullOrEmpty(userId, "userId");

    width = Math.max(width, UNSPECIFIED_DIMENSION);
    height = Math.max(height, UNSPECIFIED_DIMENSION);

    if (width == UNSPECIFIED_DIMENSION && height == UNSPECIFIED_DIMENSION)
    {
      throw new IllegalArgumentException("Either width or height must be greater than 0");
    }

    Uri.Builder builder = new Uri.Builder().encodedPath(String.format(PROFILEPIC_URL_FORMAT, userId));

    if (height != UNSPECIFIED_DIMENSION)
    {
      builder.appendQueryParameter(HEIGHT_PARAM, String.valueOf(height));
    }

    if (width != UNSPECIFIED_DIMENSION)
    {
      builder.appendQueryParameter(WIDTH_PARAM, String.valueOf(width));
    }

    builder.appendQueryParameter(MIGRATION_PARAM, MIGRATION_VALUE);

    return new URI(builder.toString());
  }

  private ImageRequest(Builder builder)
  {
    this.context = builder.context;
    this.imageUri = builder.imageUrl;
    this.callback = builder.callback;
    this.allowCachedRedirects = builder.allowCachedRedirects;
    this.callerTag = builder.callerTag == null ? new Object() : builder.callerTag;
  }

  public Context getContext()
  {
    return context;
  }

  public URI getImageUri()
  {
    return imageUri;
  }

  public Callback getCallback()
  {
    return callback;
  }

  public boolean isCachedRedirectAllowed()
  {
    return allowCachedRedirects;
  }

  public Object getCallerTag()
  {
    return callerTag;
  }

  public static class Builder
  {
    // Required
    private Context context;
    private URI imageUrl;

    // Optional
    private Callback callback;
    private boolean allowCachedRedirects;
    private Object callerTag;

    public Builder(Context context, URI imageUrl)
    {
      Validate.notNull(imageUrl, "imageUrl");
      this.context = context;
      this.imageUrl = imageUrl;
    }

    public Builder setCallback(Callback callback)
    {
      this.callback = callback;
      return this;
    }

    public Builder setCallerTag(Object callerTag)
    {
      this.callerTag = callerTag;
      return this;
    }

    public Builder setAllowCachedRedirects(boolean allowCachedRedirects)
    {
      this.allowCachedRedirects = allowCachedRedirects;
      return this;
    }

    public ImageRequest build()
    {
      return new ImageRequest(this);
    }
  }
}
